Electrical controlling device



Dec. 1, 1936. H. A. WILHELM 2,062,345

ELECTRICAL CONTROLLING DEVICE Filed Sept. 27, 1934 r/M/e/vosrar J NI "EN TOR.

n wwz W ATTORNEYS Patented Dec. 1, 1936 UNITED STATE ENT 4L Claims.

This invention relates to improvements in elec-= trical controlling devices.

It is one of the objects of the present invention to provide an improved electrical controlling de- 5 vice which is adapted to be used for the purpose of controlling an electric heater or cooler; an electrically operated damper, valve, pilot switch, or the like; an electric motor; or any device requiring a similar type of control.

Heretoforait has been necessa y, particularly in heating or cooling systems embodying thermo-= stats, to utilize a step-down transformer for the purpose of reducing the voltage thru the thermostat. The present controlling device can be connected directlylwith standard voltage outlets of, for example, 110 volts; and it is a further object of this invention to provide a construction in which, notwithstanding said direct connection of the control, the voltage thru the thermostat is low, so that ordinary bell wiring can be employed.

A more specific object of the invention is to provide an electrical controlling device embody= ing a magnetic core with three legs, the center leg having a primary coil thereon connectible with current of any desired voltage and having an armature pivoted thereto, and the other legs having secondary coils thereon which are in the cin- .cult with a thermostat or the like, the armature being movable in a selected direction upon energization of the primary coil, depending upon which secondary coil is short circuited.

A further object of the invention is to provide an electrical controlling device which is simple in construction, positive in operation, inexpensive,

85 and well adapted for the purpose described.

With the above and other objects in view, the invention consists of the improved electrical con trolling device and all its parts andcombinations as set forth in the claims and all equivalents 40 thereof.

In the accompanying drawing, illustrating one complete embodiment of the preferred form of the invention and one typical hook-up, the single figure illustrates a diagrammatic view of the 45 hook-up with the improved controlling device shown in elevation.

Referring more particularly to the drawing, the controlling device comprises a magnetic core I having a center leg 2 and outer legs 3 and 4.

50 An armature 6 is preferably pivotally connected to the center leg as at 5, but it may be mounted in other ways or connected to any support to provide for pivotal or sliding movement. The said armature has one end 1 adapted to be moved into 66 engagement with the leg 3 and another end 8 (Cl. L VE-$) movable into engagement with the leg 4. Each of said legs is preferably provided with a shading coil 9 which sets up a flux during the ofi period of the cycle to prevent vibration hum.

A contact strip to has one end pivotally con 5 heated to the insulated top portion 6' of the armature as at M and has its other end engageable with a complementary contact i2, which contact may lead to a cooler H3 or other electrically operated device. no

A similar contact strip it is pivotally connected as at 115 near the other end of the armature and has its outer end engageable with a contact i6 leading to the circuit of an electric heater or like device. Coil springs ll are positioned around 15 rods 58 between heads 59 on said rods and the contact strips ill and M respectively. When the armature makes contact with one leg, as, for example, the leg 3, the contact strip will pivot somewhat against the tension of the coil spring ill to 20 provide for yielding engagement with the contact l2.

Surrounding the core leg 2 is a primary coil till, which has lead wires 2i and 22 extending to a switch 23. Said switch is adapted to make con- 25 tact with a suitable source of alternating current of any desired voltage.

A secondary coil 23 is wound on the core leg 4, and a similar secondary coil 24 is wound on the core leg 3, said secondary coils being connected 30 by a common lead 25. The secondary coils are entirely insulated from the primary coil. The other end of the secondary coil 24 connects with a wire 26 leading to a thermostat contact 21.

The other end of the secondary coil 23 is con- 5 nected to a wire 28 leading to another thermostat contact 29. The contact lever 30 of the thermostat is connected thru a wire 3! with the wire 25 in common with both secondary coils.

A wire 32 leading from the main line leads to a switch 33, and said switch is adapted to complete a circuit to either the heater 34 thru wire 35 or to the cooler iii thru wire 36. Another wire 31 extending from the main wire 2! connects with flexible leads 38 and 39 for the contact strips M and ill respectively.

The typical system illustrated is only one use for the invention, and in the diagram a hook-up is shown for controlling the heating and cooling of a building. If it is the proper season for the heater to be utilized, the switch 33 is set in the position shown in the, figure. In order to place the controlling device in operation, the main switch 23 is closed to complete the circuit to the primary coil 20. If the thermostat lever 30 is not the armature may close on either side, depending upon which core leg, 3 or 4, offers the lowest reluctance to the magnetic flux. If the thermostat is making contact at 21, calling for increased heat in the building, this will short circuit the secondary coil 24; and due to the short circuiting of said coil, the leg 3 develops a resistance to any magnetic flux, and said magnetic flux is there fore forced into the core leg 4, causing the armature end 8 to be attracted toward said leg 4, thereby causing the contact switch I4 to make contact with the contact strip or finger l6 and complete the circuit to the heater.

As soon as the heat becomes efiective within the building, the thermostat lever 30 will start moving away from the contact 21; and when the temperature in the building has risen to a predetermined point, the thermostat lever 30 will ultimately make contact with the point 29, thereby short circuiting the coil 23 of the core leg 4. This short circuiting thereby sets up a resistance to the magnetic flux in said leg and causes said flux to travel over to the leg 3 and move the armature in a reverse direction or to the position shown in the figure. This will break the circuit to the electric heater. When the room temperature again becomes cool, requiring additional heat, the cycle will be repeated.

In the summer time when the cooling system is to be rendered effective, the switch 33 is moved from the position shown in-the drawing to make contact with the wire 36. When said switch is in this position, the operation of the thermostat and controlling device will serve to make and break the connection with contact I! of the cooling system. These operations will be carried out in the same manner above described in connection with the heater.

Due to the fact that the secondary coils are not connected with the main line, they can be designed to operate at a low, induced voltage of 25 volts or less, thereby permitting the use of a low voltage thermostat and low voltage wiring. In place of the thermostat, a pressure gage or equivalent switch may be substituted.

The controlling device may be used as a double-throw relay and may have more than two insulated contact fingers on each end, and it may operate as a pilot switch or direct control for an electric motor or heating apparatus.

Various other adaptations of the invention are possible, and, also, various changes and modiflcations may be made in the controlling device or system without departing from the spirit of the invention; and all of such adaptations and changes or modifications are contemplated as may come within the scope oi. the claims.

What I claim is:

1. In combination with a pair of electrically operated units and circuits therefor, a common electrical controlling device for said two circuits comprising a metallic core provided with three legs, a primary coil wound on the center leg of said core, a secondary coil wound on each of the other legs of said core, an armature intermediately pivoted to the center leg of the core and having one end movable toward one of the secondary carrying legs of the core and having its other end movable toward the other of the secondary carrying legs of the core, means for short circuiting one or the other of said secondary coils to create a reluctance to magnetic flux in the core leg on which said short circuited secondary .coil is wound, when the primary coil is enermaking contact with either of the points 21 or 29,

gized, to thereby force the magnetic flux into the other secondary carrying core leg to attract the armature to said latter leg, a single switch means for selectively placing the circuit to one or the other of said electrically operated units in condition for operation, contact means in connection with one end of the armature for controllingthe circuit to. the unit which has been selected, and contact means in connection with the other end of the armature for controlling the circuit to the other electrically operated unit when said unit has been selected.

2. In combination with a pair of electrically operated units and circuits therefor, a common electrical controlling device for said two circuits comprising a metallic core provided with three legs, a primary coil wound on the center leg of said core, a secondary coil wound on each of the other legs of said core, an armature intermediately pivoted to the center leg of the core' and having one end movable toward one of the secondary carrying legs of the core and having its other end movable toward the other of the secondary carrying legs of the core, means for short circuiting one or the other of said secondary coils to create a reluctance to magnetic flux in the core leg on which said short circuited secondary coil is wound, when the primary coil is energized, to thereby force the magnetic flux into the other secondary carrying core leg to attract the armature to said latter leg, a single switch means for selectively placing the circuit to one or the other of said electrically operated units in condition for operation, contact means in connection with one end of the armature for controlling the circuit to the unit which has been selected, contact means in connection with the other end of the armature for controlling the circuit to the other electrically operated unit when said unit has been selected, and a common electrical connection betweensaid two contact means and the source of current.

3. In combination with a pair of electrically operated units and circuits therefor, a common electrical controlling device for said two circuits comprising a metallic core provided with three legs, a primary coil wound on the center leg of said core;a pair of conductors leading from said primary coil to a source of current, a secondary coil wound on each of the other legs of said core, an armature intermediately pivoted to the center leg of the core and having one end movable toward one of the secondary carrying legs of the core and having its other end movable toward the other of the secondary carrying legs of the core, common thermostatic means for short circuiting one or the other of said secondary coils to create a reluctance to magnetic flux in the core leg on which said short circuited secondary coil is wound, when the primary coil is energized,

to thereby force the magnetic flux into the other.

secondary carrying core leg to attract the armature to said latter leg, a single switch means for selectively placing the circuit to one or the other of said electrically operated units in condition for operation, contact means in connection with one end of the armature for controlling the circuit to the unit which has been selected, and contact means in connection with the other end of the armature for controlling the circuit to the other electrically operated unit when said unit has been selected.

4. In combination with a pair of electrically operated units, a common electrical controlling device tor said two units comprising a metallic e ooo ecc 3 core provided with three legs, primary coil Wound on the center leg of said core, a pair or conciuctors ieading from said primary coil to e source of current, a secondary coii wouooi on each of the other ices of saidi core, on armature intermeriieteiy pivoted tothe center ice of the secondary carrying core ice to ture to iotter ieg, selective cw roovcioie contact member esrfi i contacts-5, e conductor connect eaici contact member with one or the conductors fieooltrig rrom the primary coii to the source, or contact member in connection with. each end of the armature, a common ccmoiuctor connecting said two contact members with the other conductor leading trom the primary coil to the source, a fixed contact member ccopcreole with the con-= tact member each emi or the armature, means eiectric iiy connecting one of said fixed coowith one of the electrically cow. units the othe f ied contact member I other electric-a y operated unit, one of eiectricaiiy operctec, aiso eiectri rooted to one or Me celecfive switch d the other of said eiec trim the contacts 

